Abstract : The development of a Fourier spectrometer employing a spherical lamellar grating, and the results of investigations of spectra and submillimeter wave harmonics of klystrons, obtained with the new instrument, are described. A novel optical system for matching an f/33 long absorption cell with an f/4 spectrometer and results of emission and absorption measurements of air in the long cell, and the absorption of 92 meter-atmospheres of pure CO2, are described in an appended reprint. A Bibliography of publications resulting from Air Force-sponsored research, from 1956 to 1970, is included. (Author)